In a battery module for an electric automobile or a hybrid vehicle, electric cells are arranged side-by-side and each have an electrode face provided with positive and negative electrode terminals. In this type of battery module, the electric cells are thus electrically connected to each other by using electrically conductive connection members (bus bars) to connect positive electrode terminals (cathode terminals) and negative electrode terminals (anode terminals) that are adjacent to each other.
A wiring module used to connect electric cells includes an insulating holding member (resin protector) that holds a group of bus bars. One example of this type of wiring module is covered by an insulating cover so that after attachment to the electric cell group, and after the adjacent electrode terminals are electrically connected to each other, the electrode terminals, the bus bars, and the like are insulated from other components, tools, and the like, and the protrusion of electrical wires is prevented, for example (JP 2013-37986A). The cover is fixed to the resin protector by a locking portion provided in the resin protector being locked to a lock-receiving portion provided in the cover. This locking structure is provided on a side face of the wiring module (a face that intersects the electrode faces).
Incidentally, technology has been proposed for enabling the resin protector to extend and retract in the electrode terminal connection direction in order to prevent problems in the assembly of the electrode terminals and the bus bars that are caused by assembly tolerance or dimensional tolerance of the electric cells and the resin protector, for example.
If the resin protector is capable of extending and retracting so as to have a variable length dimension in this way, the position of the locking portion of the resin protector changes, and therefore the cover is also required to have a configuration capable of accommodating a change in the locking position. For example, it is necessary to divide the cover into multiple pieces and provide the locking structure with a means for adjusting the locking position.